Meet Alison Levine, the only American to follow the route of Reinhold Messner to the South Pole, and one of the few to complete the Adventure Grand Slam--climbing the 7 highest peaks in the world, and skiing to both the North and South Poles. Alison has written a book about leadership with lessons from these extreme environments, called "On the Edge." She tells us what it takes to make it in extreme conditions--and everyday ones.